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Title: Effects of using two- versus three-dimensional computational modeling of fluidized beds Part I, hydrodynamics

Simulations of fluidized beds are performed to study and determine the effect on the use of coordinate systems and geometrical configurations to model fluidized bed reactors. Computational fluid dynamics is employed for an Eulerian-Eulerian model, which represents each phase as an interspersed continuum. The transport equation for granular temperature is solved and a hyperbolic tangent function is used to provide a smooth transition between the plastic and viscous regimes for the solid phase. The aim of the present work is to show the range of validity for employing simulations based on a 2D Cartesian coordinate system to approximate both cylindrical and rectangular fluidized beds. Three different fluidization regimes, bubbling, slugging and turbulent regimes, are investigated and the results of 2D and 3D simulations are presented for both cylindrical and rectangular domains. The results demonstrate that a 2D Cartesian system can be used to successfully simulate and predict a bubbling regime. However, caution must be exercised when using 2D Cartesian coordinates for other fluidized regimes. A budget analysis that explains all the differences in detail is presented in Part II [N. Xie, F. Battaglia, S. Pannala, Effects of Using Two-Versus Three-Dimensional Computational Modeling of Fluidized Beds: Part II, budget analysis, 182more » (1) (2007) 14] to complement the hydrodynamic theory of this paper.« less
Authors:
 [1] ;  [1] ;  [2]
  1. Iowa State University
  2. ORNL
Publication Date:
OSTI Identifier:
931149
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Powder Technology; Journal Volume: 182; Journal Issue: 1
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
FE USDOE - Office of Fossil Energy (FE)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 01 COAL, LIGNITE, AND PEAT; CARTESIAN COORDINATES; COMPUTERIZED SIMULATION; FLUID MECHANICS; FLUIDIZED BEDS; HYDRODYNAMICS; FLOW MODELS; TWO-DIMENSIONAL CALCULATIONS; THREE-DIMENSIONAL CALCULATIONS; CYLINDRICAL CONFIGURATION; RECTANGULAR CONFIGURATION